Text only | Text with Images

Olimex Support Forum

OLinuXino Android / Linux boards and System On Modules => A20 => Topic started by: lucacarone on January 12, 2018, 12:45:56 PM

Title: Hardware Test after replacement of A20 chip
Post by: lucacarone on January 12, 2018, 12:45:56 PM
Hi all,
we are using an A20-Lime for a prototype. We have replaced the A20 chip with a different A20 chip.
Are there methods to test hardware BGA connections? May it be with JTAG port?
Regards, Luca
Title: Re: Hardware Test after replacement of A20 chip
Post by: LubOlimex on January 12, 2018, 01:15:58 PM
Just write software test that includes sub-routines for all hardware peripherals and interfaces that you need.

If you have access to PCB xray use that to confirm if the placement and soldering of the BGA chip was successful.
Title: Re: Hardware Test after replacement of A20 chip
Post by: lucacarone on January 12, 2018, 01:55:23 PM
Unfortunately we do not have X-ray machines.
The card does not boot from SD, so I can not run any software.
Regards, Luca
Title: Re: Hardware Test after replacement of A20 chip
Post by: LubOlimex on January 12, 2018, 04:01:25 PM
Did you perform some measurements of power lines around the processor? Refer to the schematic of the board on where to measure.

Is there something over the serial debug port? Or just nothing?
Title: Re: Hardware Test after replacement of A20 chip
Post by: lucacarone on January 12, 2018, 04:25:27 PM
Ok, now We are checking power lines around the processor.

QuoteIs there something over the serial debug port? Or just nothing?
We don't see nothing on serial debug port.
Thanks for your support
Title: Re: Hardware Test after replacement of A20 chip
Post by: JohnS on January 12, 2018, 04:46:20 PM
You might think hard about how the CPU starts/boots.

So, study BROM and FEL etc.

If designing etc with BGA was trivial we'd all do it but instead most buy a board from Olimex or the like :)

John
Text only | Text with Images